Add initial implementation of API, database, and user management components.

MikrocopApi/Middleware/ExceptionHandlingMiddleware.cs

@@ -0,0 +1,42 @@
+using Microsoft.AspNetCore.Mvc;
+using MikrocopApi.Exceptions;
+
+namespace MikrocopApi.Middleware;
+
+public sealed class ExceptionHandlingMiddleware
+{
+    private readonly RequestDelegate _next;
+
+    public ExceptionHandlingMiddleware(RequestDelegate next)
+    {
+        _next = next;
+    }
+
+    public async Task InvokeAsync(HttpContext context)
+    {
+        try
+        {
+            await _next(context);
+        }
+        catch (AppException ex)
+        {
+            context.Response.StatusCode = ex.StatusCode;
+            await context.Response.WriteAsJsonAsync(new ProblemDetails
+            {
+                Title = ex.Title,
+                Detail = ex.Message,
+                Status = ex.StatusCode
+            });
+        }
+        catch (Exception)
+        {
+            context.Response.StatusCode = StatusCodes.Status500InternalServerError;
+            await context.Response.WriteAsJsonAsync(new ProblemDetails
+            {
+                Title = "Internal Server Error",
+                Detail = "An unexpected error occurred.",
+                Status = StatusCodes.Status500InternalServerError
+            });
+        }
+    }
+}